This is for my statistics class
P(A) is .7, P(B) is .25, P(A and B) is .05
I need to find P(A not B) and as far as I know, it should be 0.5/.7 and that is .071 and my book says the answer is 0.65. How do I get that answer?
How about the P(not A nor B)??
P(A) is .7, P(B) is .25, P(A and B) is .05
I need to find P(A not B) and as far as I know, it should be 0.5/.7 and that is .071 and my book says the answer is 0.65. How do I get that answer?
How about the P(not A nor B)??
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Probability of A not B
= P(A - B)
= P(A) - P(A∩B) ... [This will be clear if you draw Venn disgram]
= (0.70) - (0.05)
= 0.65.
= P(A - B)
= P(A) - P(A∩B) ... [This will be clear if you draw Venn disgram]
= (0.70) - (0.05)
= 0.65.
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P(A) + P(B) + P(A and B) =1
Remember: you're looking for P(A not B). That means you're looking for no A where B also exists. P(A) is the probability of any A, including A where B exists as well as A where B does not exist.
P(A not B) = P(A) - P (A and B)
Remember: you're looking for P(A not B). That means you're looking for no A where B also exists. P(A) is the probability of any A, including A where B exists as well as A where B does not exist.
P(A not B) = P(A) - P (A and B)